Conclusion
The current study presents detailed information on drought tolerance at
germination stage in four contrasting soybean genotypes viz.,
drought-tolerant (DTP & DTL) and drought-sensitive (DSP& DSL), and
revealed the molecular mechanisms of drought tolerance. Our
transcriptomic data revealed that tolerant genotype (DTP & DTL) is less
affected compared to the sensitive genotypes by drought stress.
Moreover, out of 981 DEGs screened for candidate gene prediction
analysis, 547 exhibited significant opposite gene expression pattern
between tolerant and sensitive genotypes, and 28 of them were located on
the Chr.08 reported to possess most number of drought tolerant
QTLs/“QTL Hotspots”. Eight of these 28 genes showed non-synonymous
SNPs, and two were located within “Hotspot region” associated with
drought tolerance on Chr.08. Hence, based on the gene annotation, PPI
and sequencing analysis, ten genes including above eight genes plus two
hub genes were predicated as most possible candidate genes regulating
drought tolerance in soybean. Hence, these ten genes required functional
validation before they can be used for breeding drought tolerance in
soybean. Overall, our study provides valuable information to understand
drought tolerance mechanism, and will greatly assists in cloning
drought-tolerant genes for breeding improved soybean cultivars.